I used him in battle and the "+1 Attack Per Life Left" was not on the card. I checked my collection and it did have it. Mistake?
There has to be more than 1 card of the same clan for the bonus to come into effect. So if you had 2 Huracan cards then they'd both have their bonuses, but if you had only one Huracan card in the hand then it would not have its bonus.